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    <title>ShellCheck: SC2316 – This applies local to the variable named readonly, which is probably not what you want. Use a separate command or the appropriate `declare` options instead.</title>
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    <h1>SC2316 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2316">See this page on GitHub</a>
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    <h2
id="this-applies-local-to-the-variable-named-readonly-which-is-probably-not-what-you-want-use-a-separate-command-or-the-appropriate-declare-options-instead">This
applies local to the variable named readonly, which is probably not what
you want. Use a separate command or the appropriate <code>declare</code>
options instead.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2316.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">local</span> <span class="va">readonly</span> <span class="va">foo</span><span class="op">=</span>3</span>
<span id="cb1-2"><a href="SC2316.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="bu">readonly</span> <span class="va">export</span> <span class="va">bar</span><span class="op">=</span>4</span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2316.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="bu">local</span> <span class="va">foo</span><span class="op">=</span>3</span>
<span id="cb2-2"><a href="SC2316.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="bu">readonly</span> <span class="va">foo</span></span>
<span id="cb2-3"><a href="SC2316.html#cb2-3" aria-hidden="true" tabindex="-1"></a></span>
<span id="cb2-4"><a href="SC2316.html#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="bu">readonly</span> <span class="va">bar</span><span class="op">=</span>4</span>
<span id="cb2-5"><a href="SC2316.html#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="bu">export</span> <span class="va">bar</span></span></code></pre></div>
<p>or</p>
<pre><code>declare -r foo=3
declare -rx bar=4</code></pre>
<h3 id="rationale">Rationale:</h3>
<p>In most languages, declaration modifiers like
<code>public</code>/<code>static</code>/<code>const</code> are keywords
and you can apply multiple to any declaration.</p>
<p>In shell scripting they are instead command names, and anything after
them is an argument. This means that <code>readonly local foo</code>
will create two readonly variables: <code>local</code>, and
<code>foo</code>. Neither will be local.</p>
<p>Instead, either use multiple commands, or use a single
<code>declare</code> command with appropriate flags
(<code>declare</code> will automatically make a variable local when
invoked in a function, unless <code>-g</code> is passed to explicitly
make it global).</p>
<h3 id="exceptions">Exceptions:</h3>
<p>If you want to name your variable <code>local</code>, you can quote
it as in <code>readonly "local"</code> to make your intention clear to
ShellCheck and other humans.</p>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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